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Production of intense highly charged ion beams by IMP 14.5 GHz electron cyclotron resonance ion source

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Nuclear Science and Techniques 2000年第3期11卷 145-149页

作者： ZHAO Hong-Wei, ZHANG Zi-Min, ZHANG Xue-Zhen, ZHAO Yu-Bin, GUO xiao-Hong, LIU Zhan-Wen, LI xi-xia, wang Yi-Fang, WEI Bao-Wen (Institute of Modern Physics, the Chinese Academy of Sciences, Lanzhou 730000) 中科院近代物理所甘肃兰州 730000

A new 14.5 GHz Electron Cyclotron Resonance (ECR) ion source has been constructed over the last two years. The source was designed and tested by making use of the latest results from ECR ion source development, such as high mirror magnetic field, large plasma volume, and biased probe. 140uA of O^7+, 185uA of Ar^11+ and 50uA of Xe^26+ could be produced with a RF power of 800 W. The intense beams of highly charged metallic ions are produced by means of the method of a metal evaporation oven and volatile compound through axial access. The test results are 130uA of Ca^11+, 70uA of Ca^12+ and 65uA of Fe^lo+. The ion source has been put into operation for the cyclotron at the institute of Modern Physics (IMP).

关键词：电子回旋加速器离子源束流稳定性带电离子束金属离子 ECR

Cross-subcarrier precoder design for massive MIMO-OFDM downlink with symplectic optimization

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Science China(Information Sciences) 2025年

作者： Yu-Xuan ZHANG An-An LU xiang-Gen xia xi-Qi GAO National Mobile Communications Research Laboratory Southeast University Purple Mountain Laboratories Department of Electrical and Computer Engineering University of Delaware

We propose a cross-subcarrier precoder design(CSPD) for massive multiple-input multiple-output(MIMO) orthogonal frequency division multiplexing(OFDM) downlink. This work aims to significantly improve the channel estimation and signal detection performance by enhancing the smoothness of the frequency domain effective channel. This is accomplished by designing a few vectors known as the transform domain precoding vectors(TDPVs), which are then transformed into the frequency domain to generate the precoders for a set of subcarriers. To combat the effect of channel aging, the TDPVs are optimized under imperfect channel state information(CSI). The optimal precoder structure is derived by maximizing an upper bound of the ergodic weighted sum-rate(WSR) and utilizing the a posteriori beam-based statistical channel model(BSCM). To avoid the large-dimensional matrix inversion, we propose an algorithm with symplectic optimization. Simulation results indicate that the proposed cross-subcarrier precoder design significantly outperforms conventional methods.

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火箭助推器在空间中对雷达观测的影响

哈尔滨工业大学学报 2009年第9期41卷 6-11页

作者：夏喜旺荆武兴李超勇哈尔滨工业大学航天学院哈尔滨150001

针对运载火箭二级助推器及分离时产生的大的碎片对雷达观测可能造成的影响,阐述了雷达成像重叠轨道的概念,分析了雷达部署位置与火箭载荷轨道面的相对关系,雷达成像重叠轨道(RO IO)在空间中的确定方法,地球旋转及助推器飞行中的轨道突变... 详细信息

针对运载火箭二级助推器及分离时产生的大的碎片对雷达观测可能造成的影响,阐述了雷达成像重叠轨道的概念,分析了雷达部署位置与火箭载荷轨道面的相对关系,雷达成像重叠轨道(RO IO)在空间中的确定方法,地球旋转及助推器飞行中的轨道突变对RO IO确定的影响等.仿真结果表明,RO IO的确定取决于雷达与目标轨道面的关系及对目标轨道的观测范围,且地球自转对确定RO IO的影响很小,而助推器的轨道突变则可能加剧RO IO对雷达观测的影响.最后就如何避免RO IO对目标轨道确定所造成的干扰提出一些建议.

关键词：运载火箭二级助推器雷达成像重叠轨道角差模糊区轨道确定

Orbitronics for energy-efficient magnetization switching

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Science China(Information Sciences) 2025年第1期68卷 398-399页

作者： Yuxuan YAO Daoqian ZHU Qingtao xia Jianing LIANG Yuhao JIANG Zhiyang PENG Jiaxu LI Chen xiaO Renyou XU Wenwen wang xiantao SHANG Shiyang LU Dapeng ZHU Hong-xi LIU Kaihua CAO Weisheng ZHAO Fert Beijing Institute School of Integrated Circuit Science and Engineering Beihang University National Key Lab of Spintronics Institute of International Innovation Beihang University Qingdao Research Institute Beihang University Truth Memory Corporation

Spin-orbit torque （SOT）,as a promising writing method for magnetic random-access memory （MRAM）,has garnered widespread interest for over a decade [1].Heavy metals,such as β-W,have been broadly adopted as spin current sources,but suffer from phase change at a limited thickness,resulting in a dramatic reduction of the charge-tospin conversion efficiency θSH[2].The thickness limitation leads to stringent etching conditions and large distribution among devices,posing challenges for simultaneously satisfying SOT efficiency,etching-stop margins,and back-end-ofline （BEOL） compatibility.

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Efficient and Stable Photoassisted Lithium‑Ion Battery Enabled by Photocathode with Synergistically Boosted Carriers Dynamics

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Nano-Micro Letters 2025年第3期17卷 440-454页

作者： Zelin Ma Shiyao wang Zhuangzhuang Ma Juan Li Luomeng Zhao Zhihuan Li Shiyuan wang Yazhou Shuang Jiulong wang Fang wang Weiwei xia Jie Jian Yibo He Junjie wang Pengfei Guo Hongqiang wang State Key Laboratory of Solidification Processing Center for Nano Energy MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical University and Shaanxi Joint Laboratory of Graphene(NPU)Xi’an 710072People’s Republic of China State Key Laboratory of Solidification Processing School of Materials Science and Engineering DepartmentNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China State Key Laboratory of Solidification Processing Center of Advanced Lubrication and Seal MaterialsSchool of Materials Science and EngineeringNorthwestern Polytechnical UniversityXi’an 710072People’s Republic of China Research and Development Institute of Northwestern Polytechnical University in Shenzhen Shenzhen 518063People’s Republic of China Key Laboratory of Applied Surface and Colloid Chemistry Shaanxi Key Laboratory for Advanced Energy DevicesShaanxi Engineering Lab for Advanced Energy TechnologySchool of Materials Science and EngineeringNational Ministry of EducationShaanxi Normal UniversityXi’an 710119People’s Republic of China

Efficient and stable photocathodes with versatility are of significance in photoassisted lithium-ion batteries(PLIBs),while there is always a request on fast carrier transport in electrochemical active *** work proposes a general approach of creating bulk heterojunction to boost the carrier mobility of photocathodes by simply laser assisted embedding of plasmonic *** employed in PLIBs,it was found effective for synchronously enhanced photocharge separation and transport in light charging ***,experimental photon spectroscopy,finite difference time domain method simulation and theoretical analyses demonstrate that the improved carrier dynamics are driven by the plasmonic-induced hot electron injection from metal to TiO_(2),as well as the enhanced conductivity in TiO2 matrix due to the formation of oxygen vacancies after Schottky *** from these merits,several benchmark values in performance of TiO2-based photocathode applied in PLIBs are set,including the capacity of 276 mAh g^(−1)at 0.2 A g^(−1)under illumination,photoconversion efficiency of 1.276%at 3 A g^(−1),less capacity and Columbic efficiency loss even through 200 *** results exemplify the potential of the bulk heterojunction strategy in developing highly efficient and stable photoassisted energy storage systems.

关键词： Photoassisted lithium-ion batteries Bulk heterojunction Carrier dynamics TiO2 nanofiber Plasmonic metal nanocrystals

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计算机模拟偏振对激光全息的影响

物理学报 2002年第5期51卷 1044-1048页

作者：苏慧敏郑锡光王霞许剑锋汪河洲中山大学超快速激光光谱学国家重点实验室广州510275

通过计算机对多束激光相干产生的空间干涉光场进行模拟 ,归纳出光束偏振态改变时 ,激光相干产生光学晶格效果的变化规律 ,提供了激光全息技术中激光束偏振态的最佳组合 ,使激光全息技术制作理想的亚微米单晶结构更方便快捷 .还通过实验... 详细信息

通过计算机对多束激光相干产生的空间干涉光场进行模拟 ,归纳出光束偏振态改变时 ,激光相干产生光学晶格效果的变化规律 ,提供了激光全息技术中激光束偏振态的最佳组合 ,使激光全息技术制作理想的亚微米单晶结构更方便快捷 .还通过实验验证了理论模拟结果。

关键词：激光全息技术偏振态光学晶格光子晶体光束偏振计算机模拟

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火箭助推器对雷达观测的影响研究

飞行力学 2009年第1期27卷 89-92页

作者：夏喜旺荆武兴李超勇哈尔滨工业大学航天工程系黑龙江哈尔滨150001

针对运载火箭二级助推器及分离时产生的大的碎片对雷达观测可能造成的影响,阐述了雷达成像重叠轨道(ROIO)的概念,并就雷达处于火箭载荷轨道平面内的情况分析了ROIO的存在条件、确定方法和观测中火箭载荷轨道及其ROIO上所对应的位置相对... 详细信息

针对运载火箭二级助推器及分离时产生的大的碎片对雷达观测可能造成的影响,阐述了雷达成像重叠轨道(ROIO)的概念,并就雷达处于火箭载荷轨道平面内的情况分析了ROIO的存在条件、确定方法和观测中火箭载荷轨道及其ROIO上所对应的位置相对于雷达的角度差。仿真结果表明,目标轨道的观测范围及雷达相对于该观测范围的距离决定了ROIO的确定。

关键词：运载火箭二级助推器雷达成像重叠轨道角度差模糊区轨道确定

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大气层外拦截器脉冲制导律

上海航天 2011年第3期28卷 17-22,72页

作者：夏喜旺荆武兴上海宇航系统工程研究所上海201108 哈尔滨工业大学航天学院黑龙江哈尔滨150001

针对大气层外拦截器(EKV)轨控发动机垂直于体轴且导引头视场角极窄的特点,提出了一种采用固定推力发动机沿视线法向方向调整拦截弹速度矢量实施轨控的脉冲制导(PG)方法。制导开始时制导系统确定制导脉冲的施加时刻及制导脉宽,并引导制... 详细信息

针对大气层外拦截器(EKV)轨控发动机垂直于体轴且导引头视场角极窄的特点,提出了一种采用固定推力发动机沿视线法向方向调整拦截弹速度矢量实施轨控的脉冲制导(PG)方法。制导开始时制导系统确定制导脉冲的施加时刻及制导脉宽,并引导制导系统选择轨控发动机执行;用施加修正制导脉冲的方式修正拦截双方地球引力加速度差对拦截效果的影响,并确定修正脉冲的施加时刻;选择修正制导脉冲施加时刻通过实施的脉冲修正方案消除末制导段的零控脱靶量。仿真结果表明:与修正的真比例导引制导相比,脉冲制导的能耗少、实施易,拦截过程中拦截双方的高度差越小,其拦截代价也越小。

关键词：大气层外拦截杀伤器脉冲制导脉冲宽度碰撞三角

2012年5月28日唐山M_S4.8地震震源机制解和震源深度精确测定

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地震 2017年第3期37卷 107-116页

作者：李赫张辉王熠熙王丽霞王宝锁高也蔡玲玲王莉婵李冬圣天津市地震局天津300201 中国地震局兰州地震研究所甘肃兰州730000 河北省地震局石家庄050021

本文采用2012年5月28日唐山M_S4.8地震的宽频带波形资料,利用CAP方法反演得到该地震震源机制解和震源深度,在此基础上,结合多种深度震相对震源深度进行精确测定。结果显示:唐山MS_4.8地震是略带正断分量的走滑型地震。最佳双力偶解节面... 详细信息

本文采用2012年5月28日唐山M_S4.8地震的宽频带波形资料,利用CAP方法反演得到该地震震源机制解和震源深度,在此基础上,结合多种深度震相对震源深度进行精确测定。结果显示:唐山MS_4.8地震是略带正断分量的走滑型地震。最佳双力偶解节面Ⅰ走向139°、倾角79°、滑动角-17°;节面Ⅱ走向232°、倾角73°、滑动角-169°;最佳震源深度为10km,属于浅源地震。从震中位置和震源机制解来分析,此次地震发震断层可能为唐山断裂。

关键词：震源机制解震源深度 CAP方法深度震相 2012年唐山Ms4.8地震